Transcranial direct current stimulation in Parkinson’s disease management

Background. Transcranial direct current stimulation (tDCS) is discussed as a promising noninvasive neuromodulation method for alleviating symptoms of Parkinson’s disease (PD). However, evidence on the efficacy of tDCS in PD remains limited in our country.

Aim. To evaluate the effect of a course of noninvasive anodal tDCS on the motor symptoms, cognitive function, and emotional state of patients with PD.

Materials and methods. Twenty-nine patients with PD (Hoehn and Yahr stages I–III), aged 45–80 years, received anodal tDCS over the dorsolateral prefrontal cortex (DLPFC) at 2 mA for 20 minutes, once daily, 5 days per week for 2 weeks (10 sessions total). Pre- and post-treatment assessments included motor function (Unified Parkinson’s Disease Rating Scale, Part III [UPDRS-III]), cognition (Montreal Cognitive Assessment [MoCA], Frontal Assessment Battery [FAB], Trail Making Test Parts A and B [TMT-A/B]), and affective measures (Apathy Scale; State-Trait Anxiety Inventory-trait and state; Geriatric Depression Scale [GDS]).

Results. After the tDCS course, there was a statistically significant improvement in cognitive measures (higher MoCA scores and shorter TMT-A/B completion times), a reduction in motor deficit (lower UPDRS-III scores), and a decrease in apathy and trait anxiety (p<0,05). No significant changes were observed on the FAB, state anxiety, or GDS. No adverse events were reported during tDCS in PD.

Conclusion. A course of tDCS appears safe and may improve cognitive, affective (apathy, anxiety), and motor symptoms in PD. Randomized, sham-controlled trials are warranted to confirm efficacy and to determine optimal stimulation parameters.